/*
 * jPOS Project [http://jpos.org]
 * Copyright (C) 2000-2015 Alejandro P. Revilla
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.jpos.iso.packager;

import org.jpos.iso.*;
import org.jpos.util.LogEvent;
import org.jpos.util.Logger;

import java.util.ArrayList;
import java.util.BitSet;
import java.util.List;
import java.util.Map;

/**
 * ISO 8583 v1987 BINARY Packager
 * customized for VISA Base1 subfields
 *
 * @author <a href="mailto:eoin.flood@orbiscom.com">Eoin Flood</a>
 * @version $Id$
 * @see ISOPackager
 * @see ISOBasePackager
 * @see ISOComponent
 */

@SuppressWarnings("unchecked")
public class Base1SubFieldPackager extends ISOBasePackager {
	// These methods are identical to ISOBasePackager
	// except that fld[1] has been replaced with fld[0]
	// and a secondard bitmap is not allowed

	protected boolean emitBitMap() {
		return fld[0] instanceof ISOBitMapPackager;
	}

	protected int getFirstField() {
		return fld[0] instanceof ISOBitMapPackager ? 1 : 0;
	}

	protected ISOFieldPackager getBitMapfieldPackager() {
		return fld[0];
	}

	/**
	 * Unpack a packed subfield into
	 * its corresponding ISOComponent
	 */

	public int unpack(ISOComponent m, byte[] b) throws ISOException {
		LogEvent evt = new LogEvent(this, "unpack");
		try {
			if (m.getComposite() != m)
				throw new ISOException("Can't call packager on non Composite");
			if (logger != null)  // save a few CPU cycle if no logger available
				evt.addMessage(ISOUtil.hexString(b));

			int consumed = 0;
			ISOBitMap bitmap = new ISOBitMap(-1);

			BitSet bmap = null;
			int maxField = fld.length;
			if (emitBitMap()) {
				consumed += getBitMapfieldPackager().unpack(bitmap, b, consumed);
				bmap = (BitSet) bitmap.getValue();
				m.set(bitmap);
				maxField = bmap.size();
			}
			for (int i = getFirstField(); i < maxField && consumed < b.length; i++) {
				if (bmap == null || bmap.get(i)) {
					ISOComponent c = fld[i].createComponent(i);
					consumed += fld[i].unpack(c, b, consumed);
					m.set(c);
				}
			}
			if (b.length != consumed) {
				evt.addMessage(
						"WARNING: unpack len=" + b.length + " consumed=" + consumed);
			}
			return consumed;
		} catch (ISOException e) {
			evt.addMessage(e);
			throw e;
		} finally {
			Logger.log(evt);
		}
	}

	/**
	 * Pack the subfield into a byte array
	 */

	public byte[] pack(ISOComponent m) throws ISOException {
		LogEvent evt = new LogEvent(this, "pack");
		try {
			ISOComponent c;
			List<byte[]> l = new ArrayList();
			Map fields = m.getChildren();
			int len = 0;

			if (emitBitMap()) {
				// BITMAP (-1 in HashTable)
				c = (ISOComponent) fields.get(-1);
				byte[] b = getBitMapfieldPackager().pack(c);
				len += b.length;
				l.add(b);
			}

			for (int i = getFirstField(); i <= m.getMaxField(); i++) {
				if ((c = (ISOComponent) fields.get(i)) != null) {
					try {
						byte[] b = fld[i].pack(c);
						len += b.length;
						l.add(b);
					} catch (Exception e) {
						evt.addMessage("error packing field " + i);
						evt.addMessage(c);
						evt.addMessage(e);
						throw new ISOException(e);
					}
				}
			}
			int k = 0;
			byte[] d = new byte[len];
			for (byte[] b : l) {
				System.arraycopy(b, 0, d, k, b.length);
				k += b.length;
			}
			if (logger != null)  // save a few CPU cycle if no logger available
				evt.addMessage(ISOUtil.hexString(d));
			return d;
		} catch (ISOException e) {
			evt.addMessage(e);
			throw e;
		} finally {
			Logger.log(evt);
		}
	}
}


